How to stop being offended?

When I stopped being offended, people stopped offending me. You might say: that doesn't happen. How can one not be offended when touched on a sensitive spot? If one understands the origins of offense, I believe there will be no reason to be offended. So, what is it within us that doesn't allow us to forgive? To forgive means not to leave a trace of bitterness in your soul, to continue communicating freely with a person. Or, if you prefer, not to communicate at all, but at the same time not to recall them harshly, that is, to remain neutral.